Zobrazeno 1 - 10
of 91
pro vyhledávání: '"Marc Gyssens"'
Publikováno v:
The Computer Journal. 64:789-811
Many graph query languages rely on composition to navigate graphs and select nodes of interest, even though evaluating compositions of relations can be costly. Often, this need for composition can be reduced by rewriting toward queries using semi-joi
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::7abbf54e5a506aba1f4a1d585f11188d
https://doi.org/10.1093/comjnl/bxaa031
https://doi.org/10.1093/comjnl/bxaa031
Publikováno v:
Lecture Notes in Computer Science ISBN: 9783031113208
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::e4850aebcf19458af8b3fbf8d60a34b9
https://doi.org/10.1007/978-3-031-11321-5_11
https://doi.org/10.1007/978-3-031-11321-5_11
Fragments of Tarski’s relation algebra form the basis of many versatile graph and tree query languages including the regular path queries, XPath, and SPARQL. Surprisingly, however, a systematic study of the relative expressive power of relation alg
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0ec09de13f752a21dd261d8129ced52a
http://hdl.handle.net/1942/37014
http://hdl.handle.net/1942/37014
Publikováno v:
Communications in Computer and Information Science ISBN: 9789811614798
The Query Reverse Engineering problem tries to discover a query that satisfies a set of examples based on data stored in a data source. Notwithstanding this problem has been an active research field in the relational database's research community dur
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::046afa8dd175a3e2d611c6669f7646b1
https://doi.org/10.1007/978-981-16-1480-4_26
https://doi.org/10.1007/978-981-16-1480-4_26
Autor:
Marc Gyssens, Dirk Van Gucht, George H. L. Fletcher, Jelle Hellings, Jan Van den Bussche, Stijn Vansummeren, Yuqing Wu
Publikováno v:
Information systems, 89
Information Systems, 89:101467. Elsevier
Information Systems, 89:101467. Elsevier
Motivated by the continuing interest in the tree data model, we study the expressive power of downward navigational query languages on trees and chains. Basic navigational queries are built from the identity relation and edge relations using composit
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cdcc6266b6d23a831c51403005c92bb8
http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/296840
http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/296840
Publikováno v:
Lecture Notes in Computer Science ISBN: 9783030399504
FoIKS
FoIKS
We show that the matrix query language \(\mathsf {MATLANG}\) corresponds to a natural fragment of the positive relational algebra on K-relations. The fragment is defined by introducing a composition operator and restricting K-relation arities to two.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::efa830157c094d9e656bd9153cfc6d4b
https://doi.org/10.1007/978-3-030-39951-1_3
https://doi.org/10.1007/978-3-030-39951-1_3
Autor:
Marc Gyssens, Guillermo R. Simari
Publikováno v:
Annals of Mathematics and Artificial Intelligence. 83:209-212
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::3678198e52e9899d0965c984954ed191
https://doi.org/10.1007/s10472-018-9595-9
https://doi.org/10.1007/s10472-018-9595-9
We show that the matrix query language $\mathsf{MATLANG}$ corresponds to a natural fragment of the positive relational algebra on $K$-relations. The fragment is defined by introducing a composition operator and restricting $K$-relation arities to two
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b5a175d905549d8914ee6f2d87407b19
Publikováno v:
Journal of computer and system sciences
Symmetric queries are introduced as queries on a sequence of sets of objects the result of which does not depend on the order of the sets. An appropriate data model is proposed, and two query languages are introduced, QuineCALC and SyCALC. They are c
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::519003f991c20f86143172a98ddd2e0a
https://hdl.handle.net/10067/1611700151162165141
https://hdl.handle.net/10067/1611700151162165141
Autor:
Marc GYSSENS
Publikováno v:
Encyclopedia of Database Systems ISBN: 9781489979933
Without abstract
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e78894e891ab289f52b748294ca79987
https://doi.org/10.1007/978-1-4614-8265-9_1236
https://doi.org/10.1007/978-1-4614-8265-9_1236